3 Histograms and scatterplots
In this section, two more kinds of graphical display are introduced – histograms in section 3.2 and scatterplots in section 3.3. Both are most commonly used with data that do not relate to separate categories, unlike pie charts and bar charts. However, as you will see, histograms do have something in common with bar charts. Scatterplots are a very common way of picturing the way in which two different quantities are related to each other.